The present invention relates in general to measuring machines, and in particular to a new and useful coordinate measureing machine made of welded steel construction and being at least partly clad in thin sheet metal shells which are spaced outwardly from the welded steel construction.
Measuring machines of the welded steel construction are known in themselves. Thus, for example, in German Pat. No. 3125681, a coordinate measuring machine is described in which the supporting base frame is formed by a welded construction on which a transverse boom carrying a spindle sleeve is movable along a steel track. The base frame of this known coordinate measuring machine consists of a resin-concrete shape in which steel tracks are inserted. The composition of the resin-concrete is chosen so that its coefficient of thermal expansion approximately corresponds to that of the adjacent steel tracks.
Now it is known that temperature fluctuations from the environment, in particular in the workshop area, very essentially affect the accuracy of measuring devices. This is true especially for coordinate measuring machines because the overall size of such machines offers large active contact surfaces.